1. Field of the Invention
This invention relates to a dual clutch control system and more particularly to a system for obtaining improved torque-transmission characteristics in an engine drive train under throttle control. The system is operative to provide improved acceleration characteristics by efficiently using the kinetic energy of rotating engine parts and provides accurate and reliable control in response to throttle changes, obtaining optimum "driver feel". The system makes efficient and reliable use of control parameters which are determined by static and dynamic characteristics of drive train components and is versatile and readily adaptable to take into consideration the characteristics of engines, clutches, transmissions and other components as well as wheel slip.
2. Background of the Prior Art
In a prior-filed copending application entitled "DUAL CLUTCH APPLICATION AREA AND CONTROL", Ser. No. 107,143, filed Oct. 9, 1987, an improved system is disclosed which is particularly advantageous for use with a high torque engine, such as a gas turbine engine, to provide an interface between the engine and the transmission in an automobile or other vehicle. As disclosed in that application, a clutch is provided having a relatively small apply area and a separate relatively large apply area to actuate the pressure plate to effect clutch engagement. Separate hydraulic systems are provided for controlling the application of hydraulic fluid pressure to the two areas. The system for the small apply area is a closed loop system with a fast response while the system for the large area is relatively slow in response. Pulse-width modulated signals may be applied to solenoid valves of the two hydraulic systems to control the pressures applied to the small apply and large apply piston areas.
Other prior art relates to clutches for continuously variable transmissions and includes applications of Petzold, et al. entitled "CONTINUOUSLY VARIABLE TRANSMISSION CLUTCH CONTROL SYSTEM", U.S. Ser. No. 025,391, filed Mar. 13, 1987, Petzold, et al. entitled "SPECIAL START TECHNIQUE FOR CONTINUOUSLY VARIABLE TRANSMISSION CLUTCH CONTROL", U.S. Ser No. 025476, filed Mar. 13, 1987, and U.S. Pat. No. 4,648,496, issued Mar. 10, 1987 to Petzold and Miller.